Peripheral Neuropathy

General

Peripheral neuropathy, a result of nerve damage, often causes weakness, numbness and pain, usually in your hands and feet, but it may also occur in other areas of your body. People generally describe the pain of peripheral neuropathy as tingling or burning, while they may compare the loss of sensation to the feeling of wearing a thin stocking or glove.

Peripheral neuropathy can result from problems such as traumatic injuries, infections, metabolic problems and exposure to toxins. One of the most common causes is diabetes.

In many cases, peripheral neuropathy symptoms improve with time, especially if the condition is caused by an underlying condition that can be treated. A number of medications are used to reduce the painful symptoms of peripheral neuropathy.

The name of the condition tells you a bit about what it is:

Peripheral: Beyond (in this case, beyond the brain and the spinal cord.) Neuro-: Related to the nerves -pathy: Disease

Peripheral neuropathy refers to the conditions that result when nerves that carry messages to the brain and spinal cord from the rest of the body are damaged or diseased.

The peripheral nerves make up an intricate network that connects the brain and spinal cord to the muscles, skin and internal organs. Peripheral nerves come out of the spinal cord and are arranged along lines in the body called dermatomes. Typically, damage to a nerve will affect one or more dermatomes, which can be tracked to specific areas of the body. Damage to these nerves interrupts communication between the brain and other parts of the body and can impair muscle movement, prevent normal sensation in the arms and legs, and cause pain. Nerves that innervate some internal organs can be affected when autonomic nerves are affected.

Types of Peripheral Neuropathy

There are several different kinds of peripheral neuropathies that stem from a variety of causes. They range from carpal tunnel syndrome (a traumatic injury common after chronic repetitive use of the hands and wrists, such as with computer use) to nerve damage linked to diabetes.

As a group, peripheral neuropathies are common, especially among people over the age of 55. All together, the conditions affect 3% to 4% of people in this group.

Neuropathies are typically classified according to the problems they cause or what is at the root of the damage. There also are terms that express how extensively the nerves have been damaged.

Mononeuropathy

Damage to a single peripheral nerve is called mononeuropathy. Physical injury or trauma such as from an accident is the most common cause. Prolonged pressure on a nerve, caused by extended periods of being sedentary (such as sitting in a wheelchair or lying in bed), or continuous, repetitive motions, can trigger a mononeuropathy. 

Carpal tunnel syndrome is a common type of mononeuropathy. It is called an overuse strain injury, which occurs when the nerve that travels through the wrist is compressed. People whose work requires repeated motions with the wrist (such as assembly-line workers, physical laborers, and those who use computer keyboards for prolonged periods) are at greater risk.

The damage to the nerve can result in numbness, tingling, unusual sensations, and pain in the first three fingers on the thumb side of the hand. The person may awaken at night with numbness in their hand or discover that when they perform activities like using a hair dryer, the numbness is more noticeable. In time, carpal tunnel injuries can weaken the muscles in the hand. You may also feel pain, tingling, or burning in your arm and shoulder.

Here are examples of other mononeuropathies that can cause weakness in the affected parts of the body, such as hands and feet:

  • Ulnar nerve palsy occurs when the nerve that passes close to the surface of the skin at the elbow is damaged. The numbness is noted in the 4th and 5th digit of the hand.
  • Radial nerve palsy is caused by injury to the nerve that runs along the underside of the arm and can occur with fractures of the bone in the upper part of the arm.
  • Peroneal nerve palsy results when the nerve at the top of the calf on the side of the knee is compressed. This leads to a condition called "foot drop," in which it becomes difficult to lift the feet.

Neuropathy can affect nerves that control muscle movement (motor nerves) and those that detect sensations such as coldness or pain (sensory nerves). In some cases, it can affect internal organs, such as the heart, blood vessels, bladder or intestines. Neuropathy that affects internal organs is called an autonomic neuropathy. This rare condition can cause low blood pressure or problems with sweating.

Polyneuropathy

Polyneuropathy accounts for the greatest number of peripheral neuropathy cases. It occurs when multiple peripheral nerves throughout the body malfunction at the same time. Polyneuropathy can have a wide variety of causes, including exposure to certain toxins such as with alcohol abuse, poor nutrition (particularly vitamin B deficiency), and complications from diseases such as cancer or kidney failure.

One of the most common forms of chronic polyneuropathy is diabetic neuropathy, a condition that occurs in people with diabetes. It is more severe in people with poorly controlled blood sugar levels. Though less common, diabetes can also cause a mononeuropathy.

Symptoms of Polyneuropathy: 

  • Gradual onset of numbness and tingling in your feet or hands, which may spread upward into your legs and arms
  • Burning pain
  • Sharp, jabbing or electric-like pain
  • Extreme sensitivity to touch, even light touch
  • Skin, hair or nail changes
  • Lack of coordination
  • Muscle weakness or paralysis if motor nerves are affected
  • Heat intolerance if autonomic nerves are affected
  • Bowel, bladder or digestive problems if autonomic nerves are affected
  • Changes in blood pressure, causing dizziness or lightheadedness, if autonomic nerves are affected

Because people with chronic polyneuropathy often lose their ability to sense temperature and pain, they can burn themselves and develop open sores as the result of injury or prolonged pressure. If the nerves serving the organs are involved, diarrhea or constipation may result, as well as loss of bowel or bladder control. Sexual dysfunction and abnormally low blood pressure also can occur.

One of the most serious polyneuropathies is Guillain-Barre syndrome, a rare disease that strikes suddenly when the body's immune system attacks nerves in the body just as they leave the spinal cord. Symptoms tend to appear quickly and worsen rapidly, sometimes leading to paralysis. Early symptoms include weakness and tingling that eventually may spread upward into the arms. Blood pressure problems, heart rhythm problems, and breathing difficulty may occur in the more severe cases. However, despite the severity of the disease, recovery rates are good when patients receive treatment early.

What Causes Peripheral Neuropathy?

There are many factors that can cause peripheral neuropathies, so it is often difficult to pinpoint the origin. Neuropathies occur by one of three methods:

Acquired neuropathies are caused by environmental factors such as toxins, trauma, illness, or infection. Known causes of acquired neuropathies include:

  • Diabetes
  • Several rare inherited diseases
  • Alcoholism
  • Poor nutrition or vitamin deficiency
  • Certain kinds of cancer and chemotherapy used to treat them
  • Conditions where nerves are mistakenly attacked by the body’s own immune system or damaged by an overaggressive response to injury
  • Certain medications
  • Kidney or thyroid disease
  • Infections such as Lyme Disease, Shingles or AIDS
  • Hereditary neuropathies are not as common. Hereditary neuropathies are diseases of the peripheral nerves that are genetically passed from parent to child. The most common of these is Charcot-Marie-Tooth disease type 1. It is characterized by weakness in the legs and, to a lesser degree, the arms -- symptoms that usually appear between mid-childhood and age 30. This disease is caused by degeneration of the insulation that normally surrounds the nerves and helps them conduct the electrical impulses needed for them to trigger muscle movement.
  • Idiopathic neuropathies are from an unknown cause. As many as one-third of all neuropathies are classified in this way.
Symptoms

The nerves of your peripheral nervous system send information from your brain and spinal cord (central nervous system) to all other parts of your body and back again.

Nerves that may be affected by peripheral neuropathy include:

  • Sensory nerves that receive sensations such as heat, pain or touch
  • Motor nerves that control how your muscles move
  • Autonomic nerves that control functions such as blood pressure, heart rate, digestion and bladder function

Most commonly, peripheral neuropathy starts in the longest nerves, which are the nerves that reach to your toes. Symptoms vary, depending on which types of nerves are affected. Signs and symptoms may include:

  • Gradual onset of numbness and tingling in your feet or hands, which may spread upward into your legs and arms
  • Burning pain
  • Sharp, jabbing or electric-like pain
  • Extreme sensitivity to touch, even light touch
  • Skin, hair or nail changes
  • Lack of coordination
  • Muscle weakness or paralysis if motor nerves are affected
  • Heat intolerance if autonomic nerves are affected
  • Bowel, bladder or digestive problems if autonomic nerves are affected
  • Changes in blood pressure, causing dizziness or lightheadedness, if autonomic nerves are affected

Peripheral neuropathy may affect one nerve (mononeuropathy), two or more nerves in different areas (multiple mononeuropathy) or many nerves (polyneuropathy).

Treatments

One goal of treatment is to manage the condition causing your neuropathy. If the underlying cause is corrected, the neuropathy often improves on its own. Another goal of treatment is to relieve the painful symptoms.

Pharmacological Intervention (Medications). Many types of medications can be used to relieve the pain of peripheral neuropathy, including:

  • Pain relievers. Mild symptoms may be relieved by over-the-counter pain medications, such as nonsteroidal anti-inflammatory drugs. For more-severe symptoms, your doctor may recommend prescription painkillers.

Medications containing opioids, such as tramadol (Ultram ER) or oxycodone (Roxicodone), can lead to dependence and addiction, so these drugs are generally prescribed only when other treatments fail.

  • Anti-seizure medications. Medications such as gabapentin (Gralise, Neurontin), topiramate (Topamax), pregabalin (Lyrica), carbamazepine (Carbatrol, Tegretol) and phenytoin (Dilantin, Phenytek) were originally developed to treat epilepsy. However, doctors often also prescribe them for nerve pain. Side effects may include drowsiness and dizziness.
  • Immunosuppressive medications. Medications to reduce your immune system's reaction, such as prednisone, cyclosporine (Sandimmune) and azathioprine (Imuran, Azasan), may help people with autoimmune conditions.
  • Capsaicin. A cream containing this naturally occurring substance found in hot peppers can cause modest improvements in peripheral neuropathy symptoms.

As with spicy foods, it may take some time and gradual exposure to get used to the hot sensation this cream creates. Generally, you have to get used to the heat or have the treatment area numbed in order to tolerate the Capsaicin treatment in a high enough concentration to be effective.

  • Lidocaine patch. This patch contains the topical anesthetic lidocaine (Xylocaine). You apply it to the area where your pain is most severe, and you can use up to four patches a day to relieve pain. Lidocaine may help reduce pain from peripheral neuropathy.
  • Antidepressants. Certain tricyclic antidepressant medications, such as amitriptyline, doxepin and nortriptyline (Aventyl, Pamelor), have been found to help relieve pain by interfering with chemical processes in your brain and spinal cord that cause you to feel pain.

The serotonin and norepinephrine reuptake inhibitor duloxetine (Cymbalta) and the extended-release antidepressant venlafaxine (Effexor XR) also may effectively treat the pain of peripheral neuropathy caused by diabetes.

Side effects may include dry mouth, nausea, drowsiness, dizziness, decreased appetite and constipation.

Neuromodulation Therapy. Modulating how the nerves in our body work either at the level of the spine or peripherally through Neuromodulation technology represents a dramatic improvement in treatment capability at Novocur. Dramatic alterations in symptoms can be obtained through the implantation of thin electrodes over affected nerves or nerve centers. These electrodes are programmable to achieve desired changes in the affected body part only. Novocur is a leader in this type of treatment often collaborating with Neurosurgeons to determine if this treatment may work for your symptoms.

Lifestyle and Home Remedies. The following suggestions can help you manage peripheral neuropathy at home on your own.

  • Take care of your feet, especially if you have diabetes. Check your feet daily for signs of blisters, cuts or calluses. Tight shoes and socks can worsen pain and tingling and may lead to sores that won't heal. Wear soft, loose cotton socks and padded shoes. You can use a semicircular hoop, which is available in medical supply stores, to keep bedcovers off hot or sensitive feet.
  • Exercise. Ask your doctor about an exercise routine that's right for you. Regular exercise, such as walking three times a week, may reduce neuropathy pain, improve your muscle strength and help control blood sugar levels.

Yoga and tai chi also have been shown to have many benefits, such as helping to control blood sugar levels in people with diabetes and improving neuropathy pain.

  • Quit smoking. Cigarette smoking can affect circulation, increasing the risk of foot problems and other neuropathy complications.
  • Eat healthy meals. If you're at high risk of neuropathy or have a chronic medical condition, healthy eating is especially important to ensure that you get essential vitamins and minerals. Emphasize low-fat meats and dairy products and include lots of fruits, vegetables and whole grains in your diet.
  • Avoid alcohol. Alcohol may worsen your peripheral neuropathy.
  • Monitor your blood glucose levels. If you have diabetes, it's important that you monitor your blood glucose levels. Keeping your blood glucose under control may help improve your neuropathy.
  • Massage your hands and feet, or have someone massage them for you. Massage helps improve circulation, stimulates nerves and may temporarily relieve pain.
  • Avoid prolonged pressure. Don't keep your knees crossed or lean on your elbows for long periods of time. Doing so may cause new nerve damage.

Our physicians at Novocur are dedicated to helping you find a solution that works.

Patient Inquiry Form

Contact a Novocur Pain Center using the form below